| 摘要 |
<p>1,174,683. Abrading lenses. CESKOSLOVENSKA AKADEMIE VED. 21 Feb., 1967 [22 Feb., 1966], No. 8142/67. Heading B3D. [Also in Division C3] A method of final grinding and polishing of a hydrophilic contact lens comprises deforming the lens at a temperature higher than its softening temperature by pressing it into a defined surface, and subjecting it to a final grinding and polishing after cooling it in its deformed state and while in such state. The lens is moulded from a monomer mixture of glycolmonomethacrylate, glycoldimethacrylate and isopropylpercarbonate and is washed in distilled water and dried. A rubber stopper heated to 150‹ C. is used to press the lens on to a ground glass plate also heated to 150‹ C. As the lens softens it flattens on to the plate and upon cooling returns the flat shape so that, upon removal from the plate, it can be ground by a planar grinding plate covered with woollen fabric impregnated with eerie oxide in xylene. The lens may be relaxed to its initial moulded shape by reheating or by contact with water or physiologic solution. In another example, the lens is deformed to a spherical or cylindrical shape for final grinding and polishing. The lens may be deformed to a second shape for treatment of its other surface.</p> |
